add ydb deps

1 files changed, 2497 insertions, 0 deletions

diff --git a/contrib/tools/python/src/Objects/object.c b/contrib/tools/python/src/Objects/object.c
new file mode 100644
index 0000000000..ca04cc192c
--- /dev/null
+++ b/contrib/tools/python/src/Objects/object.c
@@ -0,0 +1,2497 @@
+
+/* Generic object operations; and implementation of None (NoObject) */
+
+#include "Python.h"
+#include "frameobject.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef Py_REF_DEBUG
+Py_ssize_t _Py_RefTotal;
+
+Py_ssize_t
+_Py_GetRefTotal(void)
+{
+    PyObject *o;
+    Py_ssize_t total = _Py_RefTotal;
+    /* ignore the references to the dummy object of the dicts and sets
+       because they are not reliable and not useful (now that the
+       hash table code is well-tested) */
+    o = _PyDict_Dummy();
+    if (o != NULL)
+        total -= o->ob_refcnt;
+    o = _PySet_Dummy();
+    if (o != NULL)
+        total -= o->ob_refcnt;
+    return total;
+}
+#endif /* Py_REF_DEBUG */
+
+int Py_DivisionWarningFlag;
+int Py_Py3kWarningFlag;
+
+/* Object allocation routines used by NEWOBJ and NEWVAROBJ macros.
+   These are used by the individual routines for object creation.
+   Do not call them otherwise, they do not initialize the object! */
+
+#ifdef Py_TRACE_REFS
+/* Head of circular doubly-linked list of all objects.  These are linked
+ * together via the _ob_prev and _ob_next members of a PyObject, which
+ * exist only in a Py_TRACE_REFS build.
+ */
+static PyObject refchain = {&refchain, &refchain};
+
+/* Insert op at the front of the list of all objects.  If force is true,
+ * op is added even if _ob_prev and _ob_next are non-NULL already.  If
+ * force is false amd _ob_prev or _ob_next are non-NULL, do nothing.
+ * force should be true if and only if op points to freshly allocated,
+ * uninitialized memory, or you've unlinked op from the list and are
+ * relinking it into the front.
+ * Note that objects are normally added to the list via _Py_NewReference,
+ * which is called by PyObject_Init.  Not all objects are initialized that
+ * way, though; exceptions include statically allocated type objects, and
+ * statically allocated singletons (like Py_True and Py_None).
+ */
+void
+_Py_AddToAllObjects(PyObject *op, int force)
+{
+#ifdef  Py_DEBUG
+    if (!force) {
+        /* If it's initialized memory, op must be in or out of
+         * the list unambiguously.
+         */
+        assert((op->_ob_prev == NULL) == (op->_ob_next == NULL));
+    }
+#endif
+    if (force || op->_ob_prev == NULL) {
+        op->_ob_next = refchain._ob_next;
+        op->_ob_prev = &refchain;
+        refchain._ob_next->_ob_prev = op;
+        refchain._ob_next = op;
+    }
+}
+#endif  /* Py_TRACE_REFS */
+
+#ifdef COUNT_ALLOCS
+static PyTypeObject *type_list;
+/* All types are added to type_list, at least when
+   they get one object created. That makes them
+   immortal, which unfortunately contributes to
+   garbage itself. If unlist_types_without_objects
+   is set, they will be removed from the type_list
+   once the last object is deallocated. */
+static int unlist_types_without_objects;
+extern Py_ssize_t tuple_zero_allocs, fast_tuple_allocs;
+extern Py_ssize_t quick_int_allocs, quick_neg_int_allocs;
+extern Py_ssize_t null_strings, one_strings;
+void
+dump_counts(FILE* f)
+{
+    PyTypeObject *tp;
+
+    for (tp = type_list; tp; tp = tp->tp_next)
+        fprintf(f, "%s alloc'd: %" PY_FORMAT_SIZE_T "d, "
+            "freed: %" PY_FORMAT_SIZE_T "d, "
+            "max in use: %" PY_FORMAT_SIZE_T "d\n",
+            tp->tp_name, tp->tp_allocs, tp->tp_frees,
+            tp->tp_maxalloc);
+    fprintf(f, "fast tuple allocs: %" PY_FORMAT_SIZE_T "d, "
+        "empty: %" PY_FORMAT_SIZE_T "d\n",
+        fast_tuple_allocs, tuple_zero_allocs);
+    fprintf(f, "fast int allocs: pos: %" PY_FORMAT_SIZE_T "d, "
+        "neg: %" PY_FORMAT_SIZE_T "d\n",
+        quick_int_allocs, quick_neg_int_allocs);
+    fprintf(f, "null strings: %" PY_FORMAT_SIZE_T "d, "
+        "1-strings: %" PY_FORMAT_SIZE_T "d\n",
+        null_strings, one_strings);
+}
+
+PyObject *
+get_counts(void)
+{
+    PyTypeObject *tp;
+    PyObject *result;
+    PyObject *v;
+
+    result = PyList_New(0);
+    if (result == NULL)
+        return NULL;
+    for (tp = type_list; tp; tp = tp->tp_next) {
+        v = Py_BuildValue("(snnn)", tp->tp_name, tp->tp_allocs,
+                          tp->tp_frees, tp->tp_maxalloc);
+        if (v == NULL) {
+            Py_DECREF(result);
+            return NULL;
+        }
+        if (PyList_Append(result, v) < 0) {
+            Py_DECREF(v);
+            Py_DECREF(result);
+            return NULL;
+        }
+        Py_DECREF(v);
+    }
+    return result;
+}
+
+void
+inc_count(PyTypeObject *tp)
+{
+    if (tp->tp_next == NULL && tp->tp_prev == NULL) {
+        /* first time; insert in linked list */
+        if (tp->tp_next != NULL) /* sanity check */
+            Py_FatalError("XXX inc_count sanity check");
+        if (type_list)
+            type_list->tp_prev = tp;
+        tp->tp_next = type_list;
+        /* Note that as of Python 2.2, heap-allocated type objects
+         * can go away, but this code requires that they stay alive
+         * until program exit.  That's why we're careful with
+         * refcounts here.  type_list gets a new reference to tp,
+         * while ownership of the reference type_list used to hold
+         * (if any) was transferred to tp->tp_next in the line above.
+         * tp is thus effectively immortal after this.
+         */
+        Py_INCREF(tp);
+        type_list = tp;
+#ifdef Py_TRACE_REFS
+        /* Also insert in the doubly-linked list of all objects,
+         * if not already there.
+         */
+        _Py_AddToAllObjects((PyObject *)tp, 0);
+#endif
+    }
+    tp->tp_allocs++;
+    if (tp->tp_allocs - tp->tp_frees > tp->tp_maxalloc)
+        tp->tp_maxalloc = tp->tp_allocs - tp->tp_frees;
+}
+
+void dec_count(PyTypeObject *tp)
+{
+    tp->tp_frees++;
+    if (unlist_types_without_objects &&
+        tp->tp_allocs == tp->tp_frees) {
+        /* unlink the type from type_list */
+        if (tp->tp_prev)
+            tp->tp_prev->tp_next = tp->tp_next;
+        else
+            type_list = tp->tp_next;
+        if (tp->tp_next)
+            tp->tp_next->tp_prev = tp->tp_prev;
+        tp->tp_next = tp->tp_prev = NULL;
+        Py_DECREF(tp);
+    }
+}
+
+#endif
+
+#ifdef Py_REF_DEBUG
+/* Log a fatal error; doesn't return. */
+void
+_Py_NegativeRefcount(const char *fname, int lineno, PyObject *op)
+{
+    char buf[300];
+
+    PyOS_snprintf(buf, sizeof(buf),
+                  "%s:%i object at %p has negative ref count "
+                  "%" PY_FORMAT_SIZE_T "d",
+                  fname, lineno, op, op->ob_refcnt);
+    Py_FatalError(buf);
+}
+
+#endif /* Py_REF_DEBUG */
+
+void
+Py_IncRef(PyObject *o)
+{
+    Py_XINCREF(o);
+}
+
+void
+Py_DecRef(PyObject *o)
+{
+    Py_XDECREF(o);
+}
+
+PyObject *
+PyObject_Init(PyObject *op, PyTypeObject *tp)
+{
+    if (op == NULL)
+        return PyErr_NoMemory();
+    /* Any changes should be reflected in PyObject_INIT (objimpl.h) */
+    Py_TYPE(op) = tp;
+    _Py_NewReference(op);
+    return op;
+}
+
+PyVarObject *
+PyObject_InitVar(PyVarObject *op, PyTypeObject *tp, Py_ssize_t size)
+{
+    if (op == NULL)
+        return (PyVarObject *) PyErr_NoMemory();
+    /* Any changes should be reflected in PyObject_INIT_VAR */
+    op->ob_size = size;
+    Py_TYPE(op) = tp;
+    _Py_NewReference((PyObject *)op);
+    return op;
+}
+
+PyObject *
+_PyObject_New(PyTypeObject *tp)
+{
+    PyObject *op;
+    op = (PyObject *) PyObject_MALLOC(_PyObject_SIZE(tp));
+    if (op == NULL)
+        return PyErr_NoMemory();
+    return PyObject_INIT(op, tp);
+}
+
+PyVarObject *
+_PyObject_NewVar(PyTypeObject *tp, Py_ssize_t nitems)
+{
+    PyVarObject *op;
+    const size_t size = _PyObject_VAR_SIZE(tp, nitems);
+    op = (PyVarObject *) PyObject_MALLOC(size);
+    if (op == NULL)
+        return (PyVarObject *)PyErr_NoMemory();
+    return PyObject_INIT_VAR(op, tp, nitems);
+}
+
+/* for binary compatibility with 2.2 */
+#undef _PyObject_Del
+void
+_PyObject_Del(PyObject *op)
+{
+    PyObject_FREE(op);
+}
+
+/* Implementation of PyObject_Print with recursion checking */
+static int
+internal_print(PyObject *op, FILE *fp, int flags, int nesting)
+{
+    int ret = 0;
+    if (nesting > 10) {
+        PyErr_SetString(PyExc_RuntimeError, "print recursion");
+        return -1;
+    }
+    if (PyErr_CheckSignals())
+        return -1;
+#ifdef USE_STACKCHECK
+    if (PyOS_CheckStack()) {
+        PyErr_SetString(PyExc_MemoryError, "stack overflow");
+        return -1;
+    }
+#endif
+    clearerr(fp); /* Clear any previous error condition */
+    if (op == NULL) {
+        Py_BEGIN_ALLOW_THREADS
+        fprintf(fp, "<nil>");
+        Py_END_ALLOW_THREADS
+    }
+    else {
+        if (op->ob_refcnt <= 0)
+            /* XXX(twouters) cast refcount to long until %zd is
+               universally available */
+            Py_BEGIN_ALLOW_THREADS
+            fprintf(fp, "<refcnt %ld at %p>",
+                (long)op->ob_refcnt, op);
+            Py_END_ALLOW_THREADS
+        else if (Py_TYPE(op)->tp_print == NULL) {
+            PyObject *s;
+            if (flags & Py_PRINT_RAW)
+                s = PyObject_Str(op);
+            else
+                s = PyObject_Repr(op);
+            if (s == NULL)
+                ret = -1;
+            else {
+                ret = internal_print(s, fp, Py_PRINT_RAW,
+                                     nesting+1);
+            }
+            Py_XDECREF(s);
+        }
+        else
+            ret = (*Py_TYPE(op)->tp_print)(op, fp, flags);
+    }
+    if (ret == 0) {
+        if (ferror(fp)) {
+            PyErr_SetFromErrno(PyExc_IOError);
+            clearerr(fp);
+            ret = -1;
+        }
+    }
+    return ret;
+}
+
+int
+PyObject_Print(PyObject *op, FILE *fp, int flags)
+{
+    return internal_print(op, fp, flags, 0);
+}
+
+
+/* For debugging convenience.  See Misc/gdbinit for some useful gdb hooks */
+void _PyObject_Dump(PyObject* op)
+{
+    if (op == NULL)
+        fprintf(stderr, "NULL\n");
+    else {
+#ifdef WITH_THREAD
+        PyGILState_STATE gil;
+#endif
+        fprintf(stderr, "object  : ");
+#ifdef WITH_THREAD
+        gil = PyGILState_Ensure();
+#endif
+        (void)PyObject_Print(op, stderr, 0);
+#ifdef WITH_THREAD
+        PyGILState_Release(gil);
+#endif
+        /* XXX(twouters) cast refcount to long until %zd is
+           universally available */
+        fprintf(stderr, "\n"
+            "type    : %s\n"
+            "refcount: %ld\n"
+            "address : %p\n",
+            Py_TYPE(op)==NULL ? "NULL" : Py_TYPE(op)->tp_name,
+            (long)op->ob_refcnt,
+            op);
+    }
+}
+
+PyObject *
+PyObject_Repr(PyObject *v)
+{
+    if (PyErr_CheckSignals())
+        return NULL;
+#ifdef USE_STACKCHECK
+    if (PyOS_CheckStack()) {
+        PyErr_SetString(PyExc_MemoryError, "stack overflow");
+        return NULL;
+    }
+#endif
+    if (v == NULL)
+        return PyString_FromString("<NULL>");
+    else if (Py_TYPE(v)->tp_repr == NULL)
+        return PyString_FromFormat("<%s object at %p>",
+                                   Py_TYPE(v)->tp_name, v);
+    else {
+        PyObject *res;
+        /* It is possible for a type to have a tp_repr representation that
+           loops infinitely. */
+        if (Py_EnterRecursiveCall(" while getting the repr of an object"))
+            return NULL;
+        res = (*Py_TYPE(v)->tp_repr)(v);
+        Py_LeaveRecursiveCall();
+        if (res == NULL)
+            return NULL;
+#ifdef Py_USING_UNICODE
+        if (PyUnicode_Check(res)) {
+            PyObject* str;
+            str = PyUnicode_AsEncodedString(res, NULL, NULL);
+            Py_DECREF(res);
+            if (str)
+                res = str;
+            else
+                return NULL;
+        }
+#endif
+        if (!PyString_Check(res)) {
+            PyErr_Format(PyExc_TypeError,
+                         "__repr__ returned non-string (type %.200s)",
+                         Py_TYPE(res)->tp_name);
+            Py_DECREF(res);
+            return NULL;
+        }
+        return res;
+    }
+}
+
+PyObject *
+_PyObject_Str(PyObject *v)
+{
+    PyObject *res;
+    int type_ok;
+    if (v == NULL)
+        return PyString_FromString("<NULL>");
+    if (PyString_CheckExact(v)) {
+        Py_INCREF(v);
+        return v;
+    }
+#ifdef Py_USING_UNICODE
+    if (PyUnicode_CheckExact(v)) {
+        Py_INCREF(v);
+        return v;
+    }
+#endif
+    if (Py_TYPE(v)->tp_str == NULL)
+        return PyObject_Repr(v);
+
+    /* It is possible for a type to have a tp_str representation that loops
+       infinitely. */
+    if (Py_EnterRecursiveCall(" while getting the str of an object"))
+        return NULL;
+    res = (*Py_TYPE(v)->tp_str)(v);
+    Py_LeaveRecursiveCall();
+    if (res == NULL)
+        return NULL;
+    type_ok = PyString_Check(res);
+#ifdef Py_USING_UNICODE
+    type_ok = type_ok || PyUnicode_Check(res);
+#endif
+    if (!type_ok) {
+        PyErr_Format(PyExc_TypeError,
+                     "__str__ returned non-string (type %.200s)",
+                     Py_TYPE(res)->tp_name);
+        Py_DECREF(res);
+        return NULL;
+    }
+    return res;
+}
+
+PyObject *
+PyObject_Str(PyObject *v)
+{
+    PyObject *res = _PyObject_Str(v);
+    if (res == NULL)
+        return NULL;
+#ifdef Py_USING_UNICODE
+    if (PyUnicode_Check(res)) {
+        PyObject* str;
+        str = PyUnicode_AsEncodedString(res, NULL, NULL);
+        Py_DECREF(res);
+        if (str)
+            res = str;
+        else
+            return NULL;
+    }
+#endif
+    assert(PyString_Check(res));
+    return res;
+}
+
+#ifdef Py_USING_UNICODE
+PyObject *
+PyObject_Unicode(PyObject *v)
+{
+    PyObject *res;
+    PyObject *func;
+    PyObject *str;
+    int unicode_method_found = 0;
+    static PyObject *unicodestr = NULL;
+
+    if (v == NULL) {
+        res = PyString_FromString("<NULL>");
+        if (res == NULL)
+            return NULL;
+        str = PyUnicode_FromEncodedObject(res, NULL, "strict");
+        Py_DECREF(res);
+        return str;
+    } else if (PyUnicode_CheckExact(v)) {
+        Py_INCREF(v);
+        return v;
+    }
+
+    if (PyInstance_Check(v)) {
+        /* We're an instance of a classic class */
+        /* Try __unicode__ from the instance -- alas we have no type */
+        if (!unicodestr) {
+            unicodestr = PyString_InternFromString("__unicode__");
+            if (!unicodestr)
+                return NULL;
+        }
+        func = PyObject_GetAttr(v, unicodestr);
+        if (func != NULL) {
+            unicode_method_found = 1;
+            res = PyObject_CallFunctionObjArgs(func, NULL);
+            Py_DECREF(func);
+        }
+        else {
+            PyErr_Clear();
+        }
+    }
+    else {
+        /* Not a classic class instance, try __unicode__. */
+        func = _PyObject_LookupSpecial(v, "__unicode__", &unicodestr);
+        if (func != NULL) {
+            unicode_method_found = 1;
+            res = PyObject_CallFunctionObjArgs(func, NULL);
+            Py_DECREF(func);
+        }
+        else if (PyErr_Occurred())
+            return NULL;
+    }
+
+    /* Didn't find __unicode__ */
+    if (!unicode_method_found) {
+        if (PyUnicode_Check(v)) {
+            /* For a Unicode subtype that's didn't overwrite __unicode__,
+               return a true Unicode object with the same data. */
+            return PyUnicode_FromUnicode(PyUnicode_AS_UNICODE(v),
+                                         PyUnicode_GET_SIZE(v));
+        }
+        if (PyString_CheckExact(v)) {
+            Py_INCREF(v);
+            res = v;
+        }
+        else {
+            if (Py_TYPE(v)->tp_str != NULL)
+                res = (*Py_TYPE(v)->tp_str)(v);
+            else
+                res = PyObject_Repr(v);
+        }
+    }
+
+    if (res == NULL)
+        return NULL;
+    if (!PyUnicode_Check(res)) {
+        str = PyUnicode_FromEncodedObject(res, NULL, "strict");
+        Py_DECREF(res);
+        res = str;
+    }
+    return res;
+}
+#endif
+
+
+/* Helper to warn about deprecated tp_compare return values.  Return:
+   -2 for an exception;
+   -1 if v <  w;
+    0 if v == w;
+    1 if v  > w.
+   (This function cannot return 2.)
+*/
+static int
+adjust_tp_compare(int c)
+{
+    if (PyErr_Occurred()) {
+        if (c != -1 && c != -2) {
+            PyObject *t, *v, *tb;
+            PyErr_Fetch(&t, &v, &tb);
+            if (PyErr_Warn(PyExc_RuntimeWarning,
+                           "tp_compare didn't return -1 or -2 "
+                           "for exception") < 0) {
+                Py_XDECREF(t);
+                Py_XDECREF(v);
+                Py_XDECREF(tb);
+            }
+            else
+                PyErr_Restore(t, v, tb);
+        }
+        return -2;
+    }
+    else if (c < -1 || c > 1) {
+        if (PyErr_Warn(PyExc_RuntimeWarning,
+                       "tp_compare didn't return -1, 0 or 1") < 0)
+            return -2;
+        else
+            return c < -1 ? -1 : 1;
+    }
+    else {
+        assert(c >= -1 && c <= 1);
+        return c;
+    }
+}
+
+
+/* Macro to get the tp_richcompare field of a type if defined */
+#define RICHCOMPARE(t) (PyType_HasFeature((t), Py_TPFLAGS_HAVE_RICHCOMPARE) \
+             ? (t)->tp_richcompare : NULL)
+
+/* Map rich comparison operators to their swapped version, e.g. LT --> GT */
+int _Py_SwappedOp[] = {Py_GT, Py_GE, Py_EQ, Py_NE, Py_LT, Py_LE};
+
+/* Try a genuine rich comparison, returning an object.  Return:
+   NULL for exception;
+   NotImplemented if this particular rich comparison is not implemented or
+     undefined;
+   some object not equal to NotImplemented if it is implemented
+     (this latter object may not be a Boolean).
+*/
+static PyObject *
+try_rich_compare(PyObject *v, PyObject *w, int op)
+{
+    richcmpfunc f;
+    PyObject *res;
+
+    if (v->ob_type != w->ob_type &&
+        PyType_IsSubtype(w->ob_type, v->ob_type) &&
+        (f = RICHCOMPARE(w->ob_type)) != NULL) {
+        res = (*f)(w, v, _Py_SwappedOp[op]);
+        if (res != Py_NotImplemented)
+            return res;
+        Py_DECREF(res);
+    }
+    if ((f = RICHCOMPARE(v->ob_type)) != NULL) {
+        res = (*f)(v, w, op);
+        if (res != Py_NotImplemented)
+            return res;
+        Py_DECREF(res);
+    }
+    if ((f = RICHCOMPARE(w->ob_type)) != NULL) {
+        return (*f)(w, v, _Py_SwappedOp[op]);
+    }
+    res = Py_NotImplemented;
+    Py_INCREF(res);
+    return res;
+}
+
+/* Try a genuine rich comparison, returning an int.  Return:
+   -1 for exception (including the case where try_rich_compare() returns an
+      object that's not a Boolean);
+    0 if the outcome is false;
+    1 if the outcome is true;
+    2 if this particular rich comparison is not implemented or undefined.
+*/
+static int
+try_rich_compare_bool(PyObject *v, PyObject *w, int op)
+{
+    PyObject *res;
+    int ok;
+
+    if (RICHCOMPARE(v->ob_type) == NULL && RICHCOMPARE(w->ob_type) == NULL)
+        return 2; /* Shortcut, avoid INCREF+DECREF */
+    res = try_rich_compare(v, w, op);
+    if (res == NULL)
+        return -1;
+    if (res == Py_NotImplemented) {
+        Py_DECREF(res);
+        return 2;
+    }
+    ok = PyObject_IsTrue(res);
+    Py_DECREF(res);
+    return ok;
+}
+
+/* Try rich comparisons to determine a 3-way comparison.  Return:
+   -2 for an exception;
+   -1 if v  < w;
+    0 if v == w;
+    1 if v  > w;
+    2 if this particular rich comparison is not implemented or undefined.
+*/
+static int
+try_rich_to_3way_compare(PyObject *v, PyObject *w)
+{
+    static struct { int op; int outcome; } tries[3] = {
+        /* Try this operator, and if it is true, use this outcome: */
+        {Py_EQ, 0},
+        {Py_LT, -1},
+        {Py_GT, 1},
+    };
+    int i;
+
+    if (RICHCOMPARE(v->ob_type) == NULL && RICHCOMPARE(w->ob_type) == NULL)
+        return 2; /* Shortcut */
+
+    for (i = 0; i < 3; i++) {
+        switch (try_rich_compare_bool(v, w, tries[i].op)) {
+        case -1:
+            return -2;
+        case 1:
+            return tries[i].outcome;
+        }
+    }
+
+    return 2;
+}
+
+/* Try a 3-way comparison, returning an int.  Return:
+   -2 for an exception;
+   -1 if v <  w;
+    0 if v == w;
+    1 if v  > w;
+    2 if this particular 3-way comparison is not implemented or undefined.
+*/
+static int
+try_3way_compare(PyObject *v, PyObject *w)
+{
+    int c;
+    cmpfunc f;
+
+    /* Comparisons involving instances are given to instance_compare,
+       which has the same return conventions as this function. */
+
+    f = v->ob_type->tp_compare;
+    if (PyInstance_Check(v))
+        return (*f)(v, w);
+    if (PyInstance_Check(w))
+        return (*w->ob_type->tp_compare)(v, w);
+
+    /* If both have the same (non-NULL) tp_compare, use it. */
+    if (f != NULL && f == w->ob_type->tp_compare) {
+        c = (*f)(v, w);
+        return adjust_tp_compare(c);
+    }
+
+    /* If either tp_compare is _PyObject_SlotCompare, that's safe. */
+    if (f == _PyObject_SlotCompare ||
+        w->ob_type->tp_compare == _PyObject_SlotCompare)
+        return _PyObject_SlotCompare(v, w);
+
+    /* If we're here, v and w,
+        a) are not instances;
+        b) have different types or a type without tp_compare; and
+        c) don't have a user-defined tp_compare.
+       tp_compare implementations in C assume that both arguments
+       have their type, so we give up if the coercion fails or if
+       it yields types which are still incompatible (which can
+       happen with a user-defined nb_coerce).
+    */
+    c = PyNumber_CoerceEx(&v, &w);
+    if (c < 0)
+        return -2;
+    if (c > 0)
+        return 2;
+    f = v->ob_type->tp_compare;
+    if (f != NULL && f == w->ob_type->tp_compare) {
+        c = (*f)(v, w);
+        Py_DECREF(v);
+        Py_DECREF(w);
+        return adjust_tp_compare(c);
+    }
+
+    /* No comparison defined */
+    Py_DECREF(v);
+    Py_DECREF(w);
+    return 2;
+}
+
+/* Final fallback 3-way comparison, returning an int.  Return:
+   -2 if an error occurred;
+   -1 if v <  w;
+    0 if v == w;
+    1 if v >  w.
+*/
+static int
+default_3way_compare(PyObject *v, PyObject *w)
+{
+    int c;
+    const char *vname, *wname;
+
+    if (v->ob_type == w->ob_type) {
+        /* When comparing these pointers, they must be cast to
+         * integer types (i.e. Py_uintptr_t, our spelling of C9X's
+         * uintptr_t).  ANSI specifies that pointer compares other
+         * than == and != to non-related structures are undefined.
+         */
+        Py_uintptr_t vv = (Py_uintptr_t)v;
+        Py_uintptr_t ww = (Py_uintptr_t)w;
+        return (vv < ww) ? -1 : (vv > ww) ? 1 : 0;
+    }
+
+    /* None is smaller than anything */
+    if (v == Py_None)
+        return -1;
+    if (w == Py_None)
+        return 1;
+
+    /* different type: compare type names; numbers are smaller */
+    if (PyNumber_Check(v))
+        vname = "";
+    else
+        vname = v->ob_type->tp_name;
+    if (PyNumber_Check(w))
+        wname = "";
+    else
+        wname = w->ob_type->tp_name;
+    c = strcmp(vname, wname);
+    if (c < 0)
+        return -1;
+    if (c > 0)
+        return 1;
+    /* Same type name, or (more likely) incomparable numeric types */
+    return ((Py_uintptr_t)(v->ob_type) < (
+        Py_uintptr_t)(w->ob_type)) ? -1 : 1;
+}
+
+/* Do a 3-way comparison, by hook or by crook.  Return:
+   -2 for an exception (but see below);
+   -1 if v <  w;
+    0 if v == w;
+    1 if v >  w;
+   BUT: if the object implements a tp_compare function, it returns
+   whatever this function returns (whether with an exception or not).
+*/
+static int
+do_cmp(PyObject *v, PyObject *w)
+{
+    int c;
+    cmpfunc f;
+
+    if (v->ob_type == w->ob_type
+        && (f = v->ob_type->tp_compare) != NULL) {
+        c = (*f)(v, w);
+        if (PyInstance_Check(v)) {
+            /* Instance tp_compare has a different signature.
+               But if it returns undefined we fall through. */
+            if (c != 2)
+                return c;
+            /* Else fall through to try_rich_to_3way_compare() */
+        }
+        else
+            return adjust_tp_compare(c);
+    }
+    /* We only get here if one of the following is true:
+       a) v and w have different types
+       b) v and w have the same type, which doesn't have tp_compare
+       c) v and w are instances, and either __cmp__ is not defined or
+          __cmp__ returns NotImplemented
+    */
+    c = try_rich_to_3way_compare(v, w);
+    if (c < 2)
+        return c;
+    c = try_3way_compare(v, w);
+    if (c < 2)
+        return c;
+    return default_3way_compare(v, w);
+}
+
+/* Compare v to w.  Return
+   -1 if v <  w or exception (PyErr_Occurred() true in latter case).
+    0 if v == w.
+    1 if v > w.
+   XXX The docs (C API manual) say the return value is undefined in case
+   XXX of error.
+*/
+int
+PyObject_Compare(PyObject *v, PyObject *w)
+{
+    int result;
+
+    if (v == NULL || w == NULL) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+    if (v == w)
+        return 0;
+    if (Py_EnterRecursiveCall(" in cmp"))
+        return -1;
+    result = do_cmp(v, w);
+    Py_LeaveRecursiveCall();
+    return result < 0 ? -1 : result;
+}
+
+/* Return (new reference to) Py_True or Py_False. */
+static PyObject *
+convert_3way_to_object(int op, int c)
+{
+    PyObject *result;
+    switch (op) {
+    case Py_LT: c = c <  0; break;
+    case Py_LE: c = c <= 0; break;
+    case Py_EQ: c = c == 0; break;
+    case Py_NE: c = c != 0; break;
+    case Py_GT: c = c >  0; break;
+    case Py_GE: c = c >= 0; break;
+    }
+    result = c ? Py_True : Py_False;
+    Py_INCREF(result);
+    return result;
+}
+
+/* We want a rich comparison but don't have one.  Try a 3-way cmp instead.
+   Return
+   NULL      if error
+   Py_True   if v op w
+   Py_False  if not (v op w)
+*/
+static PyObject *
+try_3way_to_rich_compare(PyObject *v, PyObject *w, int op)
+{
+    int c;
+
+    c = try_3way_compare(v, w);
+    if (c >= 2) {
+
+        /* Py3K warning if types are not equal and comparison isn't == or !=  */
+        if (Py_Py3kWarningFlag &&
+            v->ob_type != w->ob_type && op != Py_EQ && op != Py_NE &&
+            PyErr_WarnEx(PyExc_DeprecationWarning,
+                       "comparing unequal types not supported "
+                       "in 3.x", 1) < 0) {
+            return NULL;
+        }
+
+        c = default_3way_compare(v, w);
+    }
+    if (c <= -2)
+        return NULL;
+    return convert_3way_to_object(op, c);
+}
+
+/* Do rich comparison on v and w.  Return
+   NULL      if error
+   Else a new reference to an object other than Py_NotImplemented, usually(?):
+   Py_True   if v op w
+   Py_False  if not (v op w)
+*/
+static PyObject *
+do_richcmp(PyObject *v, PyObject *w, int op)
+{
+    PyObject *res;
+
+    res = try_rich_compare(v, w, op);
+    if (res != Py_NotImplemented)
+        return res;
+    Py_DECREF(res);
+
+    return try_3way_to_rich_compare(v, w, op);
+}
+
+/* Return:
+   NULL for exception;
+   some object not equal to NotImplemented if it is implemented
+     (this latter object may not be a Boolean).
+*/
+PyObject *
+PyObject_RichCompare(PyObject *v, PyObject *w, int op)
+{
+    PyObject *res;
+
+    assert(Py_LT <= op && op <= Py_GE);
+    if (Py_EnterRecursiveCall(" in cmp"))
+        return NULL;
+
+    /* If the types are equal, and not old-style instances, try to
+       get out cheap (don't bother with coercions etc.). */
+    if (v->ob_type == w->ob_type && !PyInstance_Check(v)) {
+        cmpfunc fcmp;
+        richcmpfunc frich = RICHCOMPARE(v->ob_type);
+        /* If the type has richcmp, try it first.  try_rich_compare
+           tries it two-sided, which is not needed since we've a
+           single type only. */
+        if (frich != NULL) {
+            res = (*frich)(v, w, op);
+            if (res != Py_NotImplemented)
+                goto Done;
+            Py_DECREF(res);
+        }
+        /* No richcmp, or this particular richmp not implemented.
+           Try 3-way cmp. */
+        fcmp = v->ob_type->tp_compare;
+        if (fcmp != NULL) {
+            int c = (*fcmp)(v, w);
+            c = adjust_tp_compare(c);
+            if (c == -2) {
+                res = NULL;
+                goto Done;
+            }
+            res = convert_3way_to_object(op, c);
+            goto Done;
+        }
+    }
+
+    /* Fast path not taken, or couldn't deliver a useful result. */
+    res = do_richcmp(v, w, op);
+Done:
+    Py_LeaveRecursiveCall();
+    return res;
+}
+
+/* Return -1 if error; 1 if v op w; 0 if not (v op w). */
+int
+PyObject_RichCompareBool(PyObject *v, PyObject *w, int op)
+{
+    PyObject *res;
+    int ok;
+
+    /* Quick result when objects are the same.
+       Guarantees that identity implies equality. */
+    if (v == w) {
+        if (op == Py_EQ)
+            return 1;
+        else if (op == Py_NE)
+            return 0;
+    }
+
+    res = PyObject_RichCompare(v, w, op);
+    if (res == NULL)
+        return -1;
+    if (PyBool_Check(res))
+        ok = (res == Py_True);
+    else
+        ok = PyObject_IsTrue(res);
+    Py_DECREF(res);
+    return ok;
+}
+
+/* Set of hash utility functions to help maintaining the invariant that
+    if a==b then hash(a)==hash(b)
+
+   All the utility functions (_Py_Hash*()) return "-1" to signify an error.
+*/
+
+long
+_Py_HashDouble(double v)
+{
+    double intpart, fractpart;
+    int expo;
+    long hipart;
+    long x;             /* the final hash value */
+    /* This is designed so that Python numbers of different types
+     * that compare equal hash to the same value; otherwise comparisons
+     * of mapping keys will turn out weird.
+     */
+
+    if (!Py_IS_FINITE(v)) {
+        if (Py_IS_INFINITY(v))
+            return v < 0 ? -271828 : 314159;
+        else
+            return 0;
+    }
+    fractpart = modf(v, &intpart);
+    if (fractpart == 0.0) {
+        /* This must return the same hash as an equal int or long. */
+        if (intpart > LONG_MAX/2 || -intpart > LONG_MAX/2) {
+            /* Convert to long and use its hash. */
+            PyObject *plong;                    /* converted to Python long */
+            plong = PyLong_FromDouble(v);
+            if (plong == NULL)
+                return -1;
+            x = PyObject_Hash(plong);
+            Py_DECREF(plong);
+            return x;
+        }
+        /* Fits in a C long == a Python int, so is its own hash. */
+        x = (long)intpart;
+        if (x == -1)
+            x = -2;
+        return x;
+    }
+    /* The fractional part is non-zero, so we don't have to worry about
+     * making this match the hash of some other type.
+     * Use frexp to get at the bits in the double.
+     * Since the VAX D double format has 56 mantissa bits, which is the
+     * most of any double format in use, each of these parts may have as
+     * many as (but no more than) 56 significant bits.
+     * So, assuming sizeof(long) >= 4, each part can be broken into two
+     * longs; frexp and multiplication are used to do that.
+     * Also, since the Cray double format has 15 exponent bits, which is
+     * the most of any double format in use, shifting the exponent field
+     * left by 15 won't overflow a long (again assuming sizeof(long) >= 4).
+     */
+    v = frexp(v, &expo);
+    v *= 2147483648.0;          /* 2**31 */
+    hipart = (long)v;           /* take the top 32 bits */
+    v = (v - (double)hipart) * 2147483648.0; /* get the next 32 bits */
+    x = hipart + (long)v + (expo << 15);
+    if (x == -1)
+        x = -2;
+    return x;
+}
+
+long
+_Py_HashPointer(void *p)
+{
+    long x;
+    size_t y = (size_t)p;
+    /* bottom 3 or 4 bits are likely to be 0; rotate y by 4 to avoid
+       excessive hash collisions for dicts and sets */
+    y = (y >> 4) | (y << (8 * SIZEOF_VOID_P - 4));
+    x = (long)y;
+    if (x == -1)
+        x = -2;
+    return x;
+}
+
+long
+PyObject_HashNotImplemented(PyObject *self)
+{
+    PyErr_Format(PyExc_TypeError, "unhashable type: '%.200s'",
+                 self->ob_type->tp_name);
+    return -1;
+}
+
+_Py_HashSecret_t _Py_HashSecret;
+
+long
+PyObject_Hash(PyObject *v)
+{
+    PyTypeObject *tp = v->ob_type;
+    if (tp->tp_hash != NULL)
+        return (*tp->tp_hash)(v);
+    /* To keep to the general practice that inheriting
+     * solely from object in C code should work without
+     * an explicit call to PyType_Ready, we implicitly call
+     * PyType_Ready here and then check the tp_hash slot again
+     */
+    if (tp->tp_dict == NULL) {
+        if (PyType_Ready(tp) < 0)
+            return -1;
+        if (tp->tp_hash != NULL)
+            return (*tp->tp_hash)(v);
+    }
+    if (tp->tp_compare == NULL && RICHCOMPARE(tp) == NULL) {
+        return _Py_HashPointer(v); /* Use address as hash value */
+    }
+    /* If there's a cmp but no hash defined, the object can't be hashed */
+    return PyObject_HashNotImplemented(v);
+}
+
+PyObject *
+PyObject_GetAttrString(PyObject *v, const char *name)
+{
+    PyObject *w, *res;
+
+    if (Py_TYPE(v)->tp_getattr != NULL)
+        return (*Py_TYPE(v)->tp_getattr)(v, (char*)name);
+    w = PyString_InternFromString(name);
+    if (w == NULL)
+        return NULL;
+    res = PyObject_GetAttr(v, w);
+    Py_XDECREF(w);
+    return res;
+}
+
+int
+PyObject_HasAttrString(PyObject *v, const char *name)
+{
+    PyObject *res = PyObject_GetAttrString(v, name);
+    if (res != NULL) {
+        Py_DECREF(res);
+        return 1;
+    }
+    PyErr_Clear();
+    return 0;
+}
+
+int
+PyObject_SetAttrString(PyObject *v, const char *name, PyObject *w)
+{
+    PyObject *s;
+    int res;
+
+    if (Py_TYPE(v)->tp_setattr != NULL)
+        return (*Py_TYPE(v)->tp_setattr)(v, (char*)name, w);
+    s = PyString_InternFromString(name);
+    if (s == NULL)
+        return -1;
+    res = PyObject_SetAttr(v, s, w);
+    Py_XDECREF(s);
+    return res;
+}
+
+PyObject *
+PyObject_GetAttr(PyObject *v, PyObject *name)
+{
+    PyTypeObject *tp = Py_TYPE(v);
+
+    if (!PyString_Check(name)) {
+#ifdef Py_USING_UNICODE
+        /* The Unicode to string conversion is done here because the
+           existing tp_getattro slots expect a string object as name
+           and we wouldn't want to break those. */
+        if (PyUnicode_Check(name)) {
+            name = _PyUnicode_AsDefaultEncodedString(name, NULL);
+            if (name == NULL)
+                return NULL;
+        }
+        else
+#endif
+        {
+            PyErr_Format(PyExc_TypeError,
+                         "attribute name must be string, not '%.200s'",
+                         Py_TYPE(name)->tp_name);
+            return NULL;
+        }
+    }
+    if (tp->tp_getattro != NULL)
+        return (*tp->tp_getattro)(v, name);
+    if (tp->tp_getattr != NULL)
+        return (*tp->tp_getattr)(v, PyString_AS_STRING(name));
+    PyErr_Format(PyExc_AttributeError,
+                 "'%.50s' object has no attribute '%.400s'",
+                 tp->tp_name, PyString_AS_STRING(name));
+    return NULL;
+}
+
+int
+PyObject_HasAttr(PyObject *v, PyObject *name)
+{
+    PyObject *res = PyObject_GetAttr(v, name);
+    if (res != NULL) {
+        Py_DECREF(res);
+        return 1;
+    }
+    PyErr_Clear();
+    return 0;
+}
+
+int
+PyObject_SetAttr(PyObject *v, PyObject *name, PyObject *value)
+{
+    PyTypeObject *tp = Py_TYPE(v);
+    int err;
+
+    if (!PyString_Check(name)){
+#ifdef Py_USING_UNICODE
+        /* The Unicode to string conversion is done here because the
+           existing tp_setattro slots expect a string object as name
+           and we wouldn't want to break those. */
+        if (PyUnicode_Check(name)) {
+            name = PyUnicode_AsEncodedString(name, NULL, NULL);
+            if (name == NULL)
+                return -1;
+        }
+        else
+#endif
+        {
+            PyErr_Format(PyExc_TypeError,
+                         "attribute name must be string, not '%.200s'",
+                         Py_TYPE(name)->tp_name);
+            return -1;
+        }
+    }
+    else
+        Py_INCREF(name);
+
+    PyString_InternInPlace(&name);
+    if (tp->tp_setattro != NULL) {
+        err = (*tp->tp_setattro)(v, name, value);
+        Py_DECREF(name);
+        return err;
+    }
+    if (tp->tp_setattr != NULL) {
+        err = (*tp->tp_setattr)(v, PyString_AS_STRING(name), value);
+        Py_DECREF(name);
+        return err;
+    }
+    Py_DECREF(name);
+    if (tp->tp_getattr == NULL && tp->tp_getattro == NULL)
+        PyErr_Format(PyExc_TypeError,
+                     "'%.100s' object has no attributes "
+                     "(%s .%.100s)",
+                     tp->tp_name,
+                     value==NULL ? "del" : "assign to",
+                     PyString_AS_STRING(name));
+    else
+        PyErr_Format(PyExc_TypeError,
+                     "'%.100s' object has only read-only attributes "
+                     "(%s .%.100s)",
+                     tp->tp_name,
+                     value==NULL ? "del" : "assign to",
+                     PyString_AS_STRING(name));
+    return -1;
+}
+
+/* Helper to get a pointer to an object's __dict__ slot, if any */
+
+PyObject **
+_PyObject_GetDictPtr(PyObject *obj)
+{
+    Py_ssize_t dictoffset;
+    PyTypeObject *tp = Py_TYPE(obj);
+
+    if (!(tp->tp_flags & Py_TPFLAGS_HAVE_CLASS))
+        return NULL;
+    dictoffset = tp->tp_dictoffset;
+    if (dictoffset == 0)
+        return NULL;
+    if (dictoffset < 0) {
+        Py_ssize_t tsize;
+        size_t size;
+
+        tsize = ((PyVarObject *)obj)->ob_size;
+        if (tsize < 0)
+            tsize = -tsize;
+        size = _PyObject_VAR_SIZE(tp, tsize);
+
+        dictoffset += (long)size;
+        assert(dictoffset > 0);
+        assert(dictoffset % SIZEOF_VOID_P == 0);
+    }
+    return (PyObject **) ((char *)obj + dictoffset);
+}
+
+PyObject *
+PyObject_SelfIter(PyObject *obj)
+{
+    Py_INCREF(obj);
+    return obj;
+}
+
+/* Helper used when the __next__ method is removed from a type:
+   tp_iternext is never NULL and can be safely called without checking
+   on every iteration.
+ */
+
+PyObject *
+_PyObject_NextNotImplemented(PyObject *self)
+{
+    PyErr_Format(PyExc_TypeError,
+                 "'%.200s' object is not iterable",
+                 Py_TYPE(self)->tp_name);
+    return NULL;
+}
+
+/* Generic GetAttr functions - put these in your tp_[gs]etattro slot */
+
+PyObject *
+_PyObject_GenericGetAttrWithDict(PyObject *obj, PyObject *name, PyObject *dict)
+{
+    PyTypeObject *tp = Py_TYPE(obj);
+    PyObject *descr = NULL;
+    PyObject *res = NULL;
+    descrgetfunc f;
+    Py_ssize_t dictoffset;
+    PyObject **dictptr;
+
+    if (!PyString_Check(name)){
+#ifdef Py_USING_UNICODE
+        /* The Unicode to string conversion is done here because the
+           existing tp_setattro slots expect a string object as name
+           and we wouldn't want to break those. */
+        if (PyUnicode_Check(name)) {
+            name = PyUnicode_AsEncodedString(name, NULL, NULL);
+            if (name == NULL)
+                return NULL;
+        }
+        else
+#endif
+        {
+            PyErr_Format(PyExc_TypeError,
+                         "attribute name must be string, not '%.200s'",
+                         Py_TYPE(name)->tp_name);
+            return NULL;
+        }
+    }
+    else
+        Py_INCREF(name);
+
+    if (tp->tp_dict == NULL) {
+        if (PyType_Ready(tp) < 0)
+            goto done;
+    }
+
+#if 0 /* XXX this is not quite _PyType_Lookup anymore */
+    /* Inline _PyType_Lookup */
+    {
+        Py_ssize_t i, n;
+        PyObject *mro, *base, *dict;
+
+        /* Look in tp_dict of types in MRO */
+        mro = tp->tp_mro;
+        assert(mro != NULL);
+        assert(PyTuple_Check(mro));
+        n = PyTuple_GET_SIZE(mro);
+        for (i = 0; i < n; i++) {
+            base = PyTuple_GET_ITEM(mro, i);
+            if (PyClass_Check(base))
+                dict = ((PyClassObject *)base)->cl_dict;
+            else {
+                assert(PyType_Check(base));
+                dict = ((PyTypeObject *)base)->tp_dict;
+            }
+            assert(dict && PyDict_Check(dict));
+            descr = PyDict_GetItem(dict, name);
+            if (descr != NULL)
+                break;
+        }
+    }
+#else
+    descr = _PyType_Lookup(tp, name);
+#endif
+
+    Py_XINCREF(descr);
+
+    f = NULL;
+    if (descr != NULL &&
+        PyType_HasFeature(descr->ob_type, Py_TPFLAGS_HAVE_CLASS)) {
+        f = descr->ob_type->tp_descr_get;
+        if (f != NULL && PyDescr_IsData(descr)) {
+            res = f(descr, obj, (PyObject *)obj->ob_type);
+            Py_DECREF(descr);
+            goto done;
+        }
+    }
+
+    if (dict == NULL) {
+        /* Inline _PyObject_GetDictPtr */
+        dictoffset = tp->tp_dictoffset;
+        if (dictoffset != 0) {
+            if (dictoffset < 0) {
+                Py_ssize_t tsize;
+                size_t size;
+
+                tsize = ((PyVarObject *)obj)->ob_size;
+                if (tsize < 0)
+                    tsize = -tsize;
+                size = _PyObject_VAR_SIZE(tp, tsize);
+
+                dictoffset += (long)size;
+                assert(dictoffset > 0);
+                assert(dictoffset % SIZEOF_VOID_P == 0);
+            }
+            dictptr = (PyObject **) ((char *)obj + dictoffset);
+            dict = *dictptr;
+        }
+    }
+    if (dict != NULL) {
+        Py_INCREF(dict);
+        res = PyDict_GetItem(dict, name);
+        if (res != NULL) {
+            Py_INCREF(res);
+            Py_XDECREF(descr);
+            Py_DECREF(dict);
+            goto done;
+        }
+        Py_DECREF(dict);
+    }
+
+    if (f != NULL) {
+        res = f(descr, obj, (PyObject *)Py_TYPE(obj));
+        Py_DECREF(descr);
+        goto done;
+    }
+
+    if (descr != NULL) {
+        res = descr;
+        /* descr was already increfed above */
+        goto done;
+    }
+
+    PyErr_Format(PyExc_AttributeError,
+                 "'%.50s' object has no attribute '%.400s'",
+                 tp->tp_name, PyString_AS_STRING(name));
+  done:
+    Py_DECREF(name);
+    return res;
+}
+
+PyObject *
+PyObject_GenericGetAttr(PyObject *obj, PyObject *name)
+{
+    return _PyObject_GenericGetAttrWithDict(obj, name, NULL);
+}
+
+int
+_PyObject_GenericSetAttrWithDict(PyObject *obj, PyObject *name,
+                                 PyObject *value, PyObject *dict)
+{
+    PyTypeObject *tp = Py_TYPE(obj);
+    PyObject *descr;
+    descrsetfunc f;
+    PyObject **dictptr;
+    int res = -1;
+
+    if (!PyString_Check(name)){
+#ifdef Py_USING_UNICODE
+        /* The Unicode to string conversion is done here because the
+           existing tp_setattro slots expect a string object as name
+           and we wouldn't want to break those. */
+        if (PyUnicode_Check(name)) {
+            name = PyUnicode_AsEncodedString(name, NULL, NULL);
+            if (name == NULL)
+                return -1;
+        }
+        else
+#endif
+        {
+            PyErr_Format(PyExc_TypeError,
+                         "attribute name must be string, not '%.200s'",
+                         Py_TYPE(name)->tp_name);
+            return -1;
+        }
+    }
+    else
+        Py_INCREF(name);
+
+    if (tp->tp_dict == NULL) {
+        if (PyType_Ready(tp) < 0)
+            goto done;
+    }
+
+    descr = _PyType_Lookup(tp, name);
+    f = NULL;
+    if (descr != NULL &&
+        PyType_HasFeature(descr->ob_type, Py_TPFLAGS_HAVE_CLASS)) {
+        f = descr->ob_type->tp_descr_set;
+        if (f != NULL && PyDescr_IsData(descr)) {
+            res = f(descr, obj, value);
+            goto done;
+        }
+    }
+
+    if (dict == NULL) {
+        dictptr = _PyObject_GetDictPtr(obj);
+        if (dictptr != NULL) {
+            dict = *dictptr;
+            if (dict == NULL && value != NULL) {
+                dict = PyDict_New();
+                if (dict == NULL)
+                    goto done;
+                *dictptr = dict;
+            }
+        }
+    }
+    if (dict != NULL) {
+        Py_INCREF(dict);
+        if (value == NULL)
+            res = PyDict_DelItem(dict, name);
+        else
+            res = PyDict_SetItem(dict, name, value);
+        if (res < 0 && PyErr_ExceptionMatches(PyExc_KeyError))
+            PyErr_SetObject(PyExc_AttributeError, name);
+        Py_DECREF(dict);
+        goto done;
+    }
+
+    if (f != NULL) {
+        res = f(descr, obj, value);
+        goto done;
+    }
+
+    if (descr == NULL) {
+        PyErr_Format(PyExc_AttributeError,
+                     "'%.100s' object has no attribute '%.200s'",
+                     tp->tp_name, PyString_AS_STRING(name));
+        goto done;
+    }
+
+    PyErr_Format(PyExc_AttributeError,
+                 "'%.50s' object attribute '%.400s' is read-only",
+                 tp->tp_name, PyString_AS_STRING(name));
+  done:
+    Py_DECREF(name);
+    return res;
+}
+
+int
+PyObject_GenericSetAttr(PyObject *obj, PyObject *name, PyObject *value)
+{
+    return _PyObject_GenericSetAttrWithDict(obj, name, value, NULL);
+}
+
+
+/* Test a value used as condition, e.g., in a for or if statement.
+   Return -1 if an error occurred */
+
+int
+PyObject_IsTrue(PyObject *v)
+{
+    Py_ssize_t res;
+    if (v == Py_True)
+        return 1;
+    if (v == Py_False)
+        return 0;
+    if (v == Py_None)
+        return 0;
+    else if (v->ob_type->tp_as_number != NULL &&
+             v->ob_type->tp_as_number->nb_nonzero != NULL)
+        res = (*v->ob_type->tp_as_number->nb_nonzero)(v);
+    else if (v->ob_type->tp_as_mapping != NULL &&
+             v->ob_type->tp_as_mapping->mp_length != NULL)
+        res = (*v->ob_type->tp_as_mapping->mp_length)(v);
+    else if (v->ob_type->tp_as_sequence != NULL &&
+             v->ob_type->tp_as_sequence->sq_length != NULL)
+        res = (*v->ob_type->tp_as_sequence->sq_length)(v);
+    else
+        return 1;
+    /* if it is negative, it should be either -1 or -2 */
+    return (res > 0) ? 1 : Py_SAFE_DOWNCAST(res, Py_ssize_t, int);
+}
+
+/* equivalent of 'not v'
+   Return -1 if an error occurred */
+
+int
+PyObject_Not(PyObject *v)
+{
+    int res;
+    res = PyObject_IsTrue(v);
+    if (res < 0)
+        return res;
+    return res == 0;
+}
+
+/* Coerce two numeric types to the "larger" one.
+   Increment the reference count on each argument.
+   Return value:
+   -1 if an error occurred;
+   0 if the coercion succeeded (and then the reference counts are increased);
+   1 if no coercion is possible (and no error is raised).
+*/
+int
+PyNumber_CoerceEx(PyObject **pv, PyObject **pw)
+{
+    register PyObject *v = *pv;
+    register PyObject *w = *pw;
+    int res;
+
+    /* Shortcut only for old-style types */
+    if (v->ob_type == w->ob_type &&
+        !PyType_HasFeature(v->ob_type, Py_TPFLAGS_CHECKTYPES))
+    {
+        Py_INCREF(v);
+        Py_INCREF(w);
+        return 0;
+    }
+    if (v->ob_type->tp_as_number && v->ob_type->tp_as_number->nb_coerce) {
+        res = (*v->ob_type->tp_as_number->nb_coerce)(pv, pw);
+        if (res <= 0)
+            return res;
+    }
+    if (w->ob_type->tp_as_number && w->ob_type->tp_as_number->nb_coerce) {
+        res = (*w->ob_type->tp_as_number->nb_coerce)(pw, pv);
+        if (res <= 0)
+            return res;
+    }
+    return 1;
+}
+
+/* Coerce two numeric types to the "larger" one.
+   Increment the reference count on each argument.
+   Return -1 and raise an exception if no coercion is possible
+   (and then no reference count is incremented).
+*/
+int
+PyNumber_Coerce(PyObject **pv, PyObject **pw)
+{
+    int err = PyNumber_CoerceEx(pv, pw);
+    if (err <= 0)
+        return err;
+    PyErr_SetString(PyExc_TypeError, "number coercion failed");
+    return -1;
+}
+
+
+/* Test whether an object can be called */
+
+int
+PyCallable_Check(PyObject *x)
+{
+    if (x == NULL)
+        return 0;
+    if (PyInstance_Check(x)) {
+        PyObject *call = PyObject_GetAttrString(x, "__call__");
+        if (call == NULL) {
+            PyErr_Clear();
+            return 0;
+        }
+        /* Could test recursively but don't, for fear of endless
+           recursion if some joker sets self.__call__ = self */
+        Py_DECREF(call);
+        return 1;
+    }
+    else {
+        return x->ob_type->tp_call != NULL;
+    }
+}
+
+/* ------------------------- PyObject_Dir() helpers ------------------------- */
+
+/* Helper for PyObject_Dir.
+   Merge the __dict__ of aclass into dict, and recursively also all
+   the __dict__s of aclass's base classes.  The order of merging isn't
+   defined, as it's expected that only the final set of dict keys is
+   interesting.
+   Return 0 on success, -1 on error.
+*/
+
+static int
+merge_class_dict(PyObject* dict, PyObject* aclass)
+{
+    PyObject *classdict;
+    PyObject *bases;
+
+    assert(PyDict_Check(dict));
+    assert(aclass);
+
+    /* Merge in the type's dict (if any). */
+    classdict = PyObject_GetAttrString(aclass, "__dict__");
+    if (classdict == NULL)
+        PyErr_Clear();
+    else {
+        int status = PyDict_Update(dict, classdict);
+        Py_DECREF(classdict);
+        if (status < 0)
+            return -1;
+    }
+
+    /* Recursively merge in the base types' (if any) dicts. */
+    bases = PyObject_GetAttrString(aclass, "__bases__");
+    if (bases == NULL)
+        PyErr_Clear();
+    else {
+        /* We have no guarantee that bases is a real tuple */
+        Py_ssize_t i, n;
+        n = PySequence_Size(bases); /* This better be right */
+        if (n < 0)
+            PyErr_Clear();
+        else {
+            for (i = 0; i < n; i++) {
+                int status;
+                PyObject *base = PySequence_GetItem(bases, i);
+                if (base == NULL) {
+                    Py_DECREF(bases);
+                    return -1;
+                }
+                status = merge_class_dict(dict, base);
+                Py_DECREF(base);
+                if (status < 0) {
+                    Py_DECREF(bases);
+                    return -1;
+                }
+            }
+        }
+        Py_DECREF(bases);
+    }
+    return 0;
+}
+
+/* Helper for PyObject_Dir.
+   If obj has an attr named attrname that's a list, merge its string
+   elements into keys of dict.
+   Return 0 on success, -1 on error.  Errors due to not finding the attr,
+   or the attr not being a list, are suppressed.
+*/
+
+static int
+merge_list_attr(PyObject* dict, PyObject* obj, const char *attrname)
+{
+    PyObject *list;
+    int result = 0;
+
+    assert(PyDict_Check(dict));
+    assert(obj);
+    assert(attrname);
+
+    list = PyObject_GetAttrString(obj, attrname);
+    if (list == NULL)
+        PyErr_Clear();
+
+    else if (PyList_Check(list)) {
+        int i;
+        for (i = 0; i < PyList_GET_SIZE(list); ++i) {
+            PyObject *item = PyList_GET_ITEM(list, i);
+            if (PyString_Check(item)) {
+                result = PyDict_SetItem(dict, item, Py_None);
+                if (result < 0)
+                    break;
+            }
+        }
+        if (Py_Py3kWarningFlag &&
+            (strcmp(attrname, "__members__") == 0 ||
+             strcmp(attrname, "__methods__") == 0)) {
+            if (PyErr_WarnEx(PyExc_DeprecationWarning,
+                           "__members__ and __methods__ not "
+                           "supported in 3.x", 1) < 0) {
+                Py_XDECREF(list);
+                return -1;
+            }
+        }
+    }
+
+    Py_XDECREF(list);
+    return result;
+}
+
+/* Helper for PyObject_Dir without arguments: returns the local scope. */
+static PyObject *
+_dir_locals(void)
+{
+    PyObject *names;
+    PyObject *locals = PyEval_GetLocals();
+
+    if (locals == NULL) {
+        PyErr_SetString(PyExc_SystemError, "frame does not exist");
+        return NULL;
+    }
+
+    names = PyMapping_Keys(locals);
+    if (!names)
+        return NULL;
+    if (!PyList_Check(names)) {
+        PyErr_Format(PyExc_TypeError,
+            "dir(): expected keys() of locals to be a list, "
+            "not '%.200s'", Py_TYPE(names)->tp_name);
+        Py_DECREF(names);
+        return NULL;
+    }
+    /* the locals don't need to be DECREF'd */
+    return names;
+}
+
+/* Helper for PyObject_Dir of type objects: returns __dict__ and __bases__.
+   We deliberately don't suck up its __class__, as methods belonging to the
+   metaclass would probably be more confusing than helpful.
+*/
+static PyObject *
+_specialized_dir_type(PyObject *obj)
+{
+    PyObject *result = NULL;
+    PyObject *dict = PyDict_New();
+
+    if (dict != NULL && merge_class_dict(dict, obj) == 0)
+        result = PyDict_Keys(dict);
+
+    Py_XDECREF(dict);
+    return result;
+}
+
+/* Helper for PyObject_Dir of module objects: returns the module's __dict__. */
+static PyObject *
+_specialized_dir_module(PyObject *obj)
+{
+    PyObject *result = NULL;
+    PyObject *dict = PyObject_GetAttrString(obj, "__dict__");
+
+    if (dict != NULL) {
+        if (PyDict_Check(dict))
+            result = PyDict_Keys(dict);
+        else {
+            char *name = PyModule_GetName(obj);
+            if (name)
+                PyErr_Format(PyExc_TypeError,
+                             "%.200s.__dict__ is not a dictionary",
+                             name);
+        }
+    }
+
+    Py_XDECREF(dict);
+    return result;
+}
+
+/* Helper for PyObject_Dir of generic objects: returns __dict__, __class__,
+   and recursively up the __class__.__bases__ chain.
+*/
+static PyObject *
+_generic_dir(PyObject *obj)
+{
+    PyObject *result = NULL;
+    PyObject *dict = NULL;
+    PyObject *itsclass = NULL;
+
+    /* Get __dict__ (which may or may not be a real dict...) */
+    dict = PyObject_GetAttrString(obj, "__dict__");
+    if (dict == NULL) {
+        PyErr_Clear();
+        dict = PyDict_New();
+    }
+    else if (!PyDict_Check(dict)) {
+        Py_DECREF(dict);
+        dict = PyDict_New();
+    }
+    else {
+        /* Copy __dict__ to avoid mutating it. */
+        PyObject *temp = PyDict_Copy(dict);
+        Py_DECREF(dict);
+        dict = temp;
+    }
+
+    if (dict == NULL)
+        goto error;
+
+    /* Merge in __members__ and __methods__ (if any).
+     * This is removed in Python 3000. */
+    if (merge_list_attr(dict, obj, "__members__") < 0)
+        goto error;
+    if (merge_list_attr(dict, obj, "__methods__") < 0)
+        goto error;
+
+    /* Merge in attrs reachable from its class. */
+    itsclass = PyObject_GetAttrString(obj, "__class__");
+    if (itsclass == NULL)
+        /* XXX(tomer): Perhaps fall back to obj->ob_type if no
+                       __class__ exists? */
+        PyErr_Clear();
+    else {
+        if (merge_class_dict(dict, itsclass) != 0)
+            goto error;
+    }
+
+    result = PyDict_Keys(dict);
+    /* fall through */
+error:
+    Py_XDECREF(itsclass);
+    Py_XDECREF(dict);
+    return result;
+}
+
+/* Helper for PyObject_Dir: object introspection.
+   This calls one of the above specialized versions if no __dir__ method
+   exists. */
+static PyObject *
+_dir_object(PyObject *obj)
+{
+    PyObject *result = NULL;
+    static PyObject *dir_str = NULL;
+    PyObject *dirfunc;
+
+    assert(obj);
+    if (PyInstance_Check(obj)) {
+        dirfunc = PyObject_GetAttrString(obj, "__dir__");
+        if (dirfunc == NULL) {
+            if (PyErr_ExceptionMatches(PyExc_AttributeError))
+                PyErr_Clear();
+            else
+                return NULL;
+        }
+    }
+    else {
+        dirfunc = _PyObject_LookupSpecial(obj, "__dir__", &dir_str);
+        if (PyErr_Occurred())
+            return NULL;
+    }
+    if (dirfunc == NULL) {
+        /* use default implementation */
+        if (PyModule_Check(obj))
+            result = _specialized_dir_module(obj);
+        else if (PyType_Check(obj) || PyClass_Check(obj))
+            result = _specialized_dir_type(obj);
+        else
+            result = _generic_dir(obj);
+    }
+    else {
+        /* use __dir__ */
+        result = PyObject_CallFunctionObjArgs(dirfunc, NULL);
+        Py_DECREF(dirfunc);
+        if (result == NULL)
+            return NULL;
+
+        /* result must be a list */
+        /* XXX(gbrandl): could also check if all items are strings */
+        if (!PyList_Check(result)) {
+            PyErr_Format(PyExc_TypeError,
+                         "__dir__() must return a list, not %.200s",
+                         Py_TYPE(result)->tp_name);
+            Py_DECREF(result);
+            result = NULL;
+        }
+    }
+
+    return result;
+}
+
+/* Implementation of dir() -- if obj is NULL, returns the names in the current
+   (local) scope.  Otherwise, performs introspection of the object: returns a
+   sorted list of attribute names (supposedly) accessible from the object
+*/
+PyObject *
+PyObject_Dir(PyObject *obj)
+{
+    PyObject * result;
+
+    if (obj == NULL)
+        /* no object -- introspect the locals */
+        result = _dir_locals();
+    else
+        /* object -- introspect the object */
+        result = _dir_object(obj);
+
+    assert(result == NULL || PyList_Check(result));
+
+    if (result != NULL && PyList_Sort(result) != 0) {
+        /* sorting the list failed */
+        Py_DECREF(result);
+        result = NULL;
+    }
+
+    return result;
+}
+
+/*
+NoObject is usable as a non-NULL undefined value, used by the macro None.
+There is (and should be!) no way to create other objects of this type,
+so there is exactly one (which is indestructible, by the way).
+(XXX This type and the type of NotImplemented below should be unified.)
+*/
+
+/* ARGSUSED */
+static PyObject *
+none_repr(PyObject *op)
+{
+    return PyString_FromString("None");
+}
+
+/* ARGUSED */
+static void
+none_dealloc(PyObject* ignore)
+{
+    /* This should never get called, but we also don't want to SEGV if
+     * we accidentally decref None out of existence.
+     */
+    Py_FatalError("deallocating None");
+}
+
+
+static PyTypeObject PyNone_Type = {
+    PyVarObject_HEAD_INIT(&PyType_Type, 0)
+    "NoneType",
+    0,
+    0,
+    none_dealloc,       /*tp_dealloc*/ /*never called*/
+    0,                  /*tp_print*/
+    0,                  /*tp_getattr*/
+    0,                  /*tp_setattr*/
+    0,                  /*tp_compare*/
+    none_repr,          /*tp_repr*/
+    0,                  /*tp_as_number*/
+    0,                  /*tp_as_sequence*/
+    0,                  /*tp_as_mapping*/
+    (hashfunc)_Py_HashPointer, /*tp_hash */
+};
+
+PyObject _Py_NoneStruct = {
+  _PyObject_EXTRA_INIT
+  1, &PyNone_Type
+};
+
+/* NotImplemented is an object that can be used to signal that an
+   operation is not implemented for the given type combination. */
+
+static PyObject *
+NotImplemented_repr(PyObject *op)
+{
+    return PyString_FromString("NotImplemented");
+}
+
+static PyTypeObject PyNotImplemented_Type = {
+    PyVarObject_HEAD_INIT(&PyType_Type, 0)
+    "NotImplementedType",
+    0,
+    0,
+    none_dealloc,       /*tp_dealloc*/ /*never called*/
+    0,                  /*tp_print*/
+    0,                  /*tp_getattr*/
+    0,                  /*tp_setattr*/
+    0,                  /*tp_compare*/
+    NotImplemented_repr, /*tp_repr*/
+    0,                  /*tp_as_number*/
+    0,                  /*tp_as_sequence*/
+    0,                  /*tp_as_mapping*/
+    0,                  /*tp_hash */
+};
+
+PyObject _Py_NotImplementedStruct = {
+    _PyObject_EXTRA_INIT
+    1, &PyNotImplemented_Type
+};
+
+void
+_Py_ReadyTypes(void)
+{
+    if (PyType_Ready(&PyType_Type) < 0)
+        Py_FatalError("Can't initialize type type");
+
+    if (PyType_Ready(&_PyWeakref_RefType) < 0)
+        Py_FatalError("Can't initialize weakref type");
+
+    if (PyType_Ready(&_PyWeakref_CallableProxyType) < 0)
+        Py_FatalError("Can't initialize callable weakref proxy type");
+
+    if (PyType_Ready(&_PyWeakref_ProxyType) < 0)
+        Py_FatalError("Can't initialize weakref proxy type");
+
+    if (PyType_Ready(&PyBool_Type) < 0)
+        Py_FatalError("Can't initialize bool type");
+
+    if (PyType_Ready(&PyString_Type) < 0)
+        Py_FatalError("Can't initialize str type");
+
+    if (PyType_Ready(&PyByteArray_Type) < 0)
+        Py_FatalError("Can't initialize bytearray type");
+
+    if (PyType_Ready(&PyList_Type) < 0)
+        Py_FatalError("Can't initialize list type");
+
+    if (PyType_Ready(&PyNone_Type) < 0)
+        Py_FatalError("Can't initialize None type");
+
+    if (PyType_Ready(&PyNotImplemented_Type) < 0)
+        Py_FatalError("Can't initialize NotImplemented type");
+
+    if (PyType_Ready(&PyTraceBack_Type) < 0)
+        Py_FatalError("Can't initialize traceback type");
+
+    if (PyType_Ready(&PySuper_Type) < 0)
+        Py_FatalError("Can't initialize super type");
+
+    if (PyType_Ready(&PyBaseObject_Type) < 0)
+        Py_FatalError("Can't initialize object type");
+
+    if (PyType_Ready(&PyRange_Type) < 0)
+        Py_FatalError("Can't initialize xrange type");
+
+    if (PyType_Ready(&PyDict_Type) < 0)
+        Py_FatalError("Can't initialize dict type");
+
+    if (PyType_Ready(&PySet_Type) < 0)
+        Py_FatalError("Can't initialize set type");
+
+#ifdef Py_USING_UNICODE
+    if (PyType_Ready(&PyUnicode_Type) < 0)
+        Py_FatalError("Can't initialize unicode type");
+#endif
+
+    if (PyType_Ready(&PySlice_Type) < 0)
+        Py_FatalError("Can't initialize slice type");
+
+    if (PyType_Ready(&PyStaticMethod_Type) < 0)
+        Py_FatalError("Can't initialize static method type");
+
+#ifndef WITHOUT_COMPLEX
+    if (PyType_Ready(&PyComplex_Type) < 0)
+        Py_FatalError("Can't initialize complex type");
+#endif
+
+    if (PyType_Ready(&PyFloat_Type) < 0)
+        Py_FatalError("Can't initialize float type");
+
+    if (PyType_Ready(&PyBuffer_Type) < 0)
+        Py_FatalError("Can't initialize buffer type");
+
+    if (PyType_Ready(&PyLong_Type) < 0)
+        Py_FatalError("Can't initialize long type");
+
+    if (PyType_Ready(&PyInt_Type) < 0)
+        Py_FatalError("Can't initialize int type");
+
+    if (PyType_Ready(&PyFrozenSet_Type) < 0)
+        Py_FatalError("Can't initialize frozenset type");
+
+    if (PyType_Ready(&PyProperty_Type) < 0)
+        Py_FatalError("Can't initialize property type");
+
+    if (PyType_Ready(&PyMemoryView_Type) < 0)
+        Py_FatalError("Can't initialize memoryview type");
+
+    if (PyType_Ready(&PyTuple_Type) < 0)
+        Py_FatalError("Can't initialize tuple type");
+
+    if (PyType_Ready(&PyEnum_Type) < 0)
+        Py_FatalError("Can't initialize enumerate type");
+
+    if (PyType_Ready(&PyReversed_Type) < 0)
+        Py_FatalError("Can't initialize reversed type");
+
+    if (PyType_Ready(&PyCode_Type) < 0)
+        Py_FatalError("Can't initialize code type");
+
+    if (PyType_Ready(&PyFrame_Type) < 0)
+        Py_FatalError("Can't initialize frame type");
+
+    if (PyType_Ready(&PyCFunction_Type) < 0)
+        Py_FatalError("Can't initialize builtin function type");
+
+    if (PyType_Ready(&PyMethod_Type) < 0)
+        Py_FatalError("Can't initialize method type");
+
+    if (PyType_Ready(&PyFunction_Type) < 0)
+        Py_FatalError("Can't initialize function type");
+
+    if (PyType_Ready(&PyClass_Type) < 0)
+        Py_FatalError("Can't initialize class type");
+
+    if (PyType_Ready(&PyDictProxy_Type) < 0)
+        Py_FatalError("Can't initialize dict proxy type");
+
+    if (PyType_Ready(&PyGen_Type) < 0)
+        Py_FatalError("Can't initialize generator type");
+
+    if (PyType_Ready(&PyGetSetDescr_Type) < 0)
+        Py_FatalError("Can't initialize get-set descriptor type");
+
+    if (PyType_Ready(&PyWrapperDescr_Type) < 0)
+        Py_FatalError("Can't initialize wrapper type");
+
+    if (PyType_Ready(&PyInstance_Type) < 0)
+        Py_FatalError("Can't initialize instance type");
+
+    if (PyType_Ready(&PyEllipsis_Type) < 0)
+        Py_FatalError("Can't initialize ellipsis type");
+
+    if (PyType_Ready(&PyMemberDescr_Type) < 0)
+        Py_FatalError("Can't initialize member descriptor type");
+
+    if (PyType_Ready(&PyFile_Type) < 0)
+        Py_FatalError("Can't initialize file type");
+
+    if (PyType_Ready(&PyCapsule_Type) < 0)
+        Py_FatalError("Can't initialize capsule type");
+
+    if (PyType_Ready(&PyCell_Type) < 0)
+        Py_FatalError("Can't initialize cell type");
+
+    if (PyType_Ready(&PyCallIter_Type) < 0)
+        Py_FatalError("Can't initialize call iter type");
+
+    if (PyType_Ready(&PySeqIter_Type) < 0)
+        Py_FatalError("Can't initialize sequence iterator type");
+}
+
+
+#ifdef Py_TRACE_REFS
+
+void
+_Py_NewReference(PyObject *op)
+{
+    _Py_INC_REFTOTAL;
+    op->ob_refcnt = 1;
+    _Py_AddToAllObjects(op, 1);
+    _Py_INC_TPALLOCS(op);
+}
+
+void
+_Py_ForgetReference(register PyObject *op)
+{
+#ifdef SLOW_UNREF_CHECK
+    register PyObject *p;
+#endif
+    if (op->ob_refcnt < 0)
+        Py_FatalError("UNREF negative refcnt");
+    if (op == &refchain ||
+        op->_ob_prev->_ob_next != op || op->_ob_next->_ob_prev != op)
+        Py_FatalError("UNREF invalid object");
+#ifdef SLOW_UNREF_CHECK
+    for (p = refchain._ob_next; p != &refchain; p = p->_ob_next) {
+        if (p == op)
+            break;
+    }
+    if (p == &refchain) /* Not found */
+        Py_FatalError("UNREF unknown object");
+#endif
+    op->_ob_next->_ob_prev = op->_ob_prev;
+    op->_ob_prev->_ob_next = op->_ob_next;
+    op->_ob_next = op->_ob_prev = NULL;
+    _Py_INC_TPFREES(op);
+}
+
+void
+_Py_Dealloc(PyObject *op)
+{
+    destructor dealloc = Py_TYPE(op)->tp_dealloc;
+    _Py_ForgetReference(op);
+    (*dealloc)(op);
+}
+
+/* Print all live objects.  Because PyObject_Print is called, the
+ * interpreter must be in a healthy state.
+ */
+void
+_Py_PrintReferences(FILE *fp)
+{
+    PyObject *op;
+    fprintf(fp, "Remaining objects:\n");
+    for (op = refchain._ob_next; op != &refchain; op = op->_ob_next) {
+        fprintf(fp, "%p [%" PY_FORMAT_SIZE_T "d] ", op, op->ob_refcnt);
+        if (PyObject_Print(op, fp, 0) != 0)
+            PyErr_Clear();
+        putc('\n', fp);
+    }
+}
+
+/* Print the addresses of all live objects.  Unlike _Py_PrintReferences, this
+ * doesn't make any calls to the Python C API, so is always safe to call.
+ */
+void
+_Py_PrintReferenceAddresses(FILE *fp)
+{
+    PyObject *op;
+    fprintf(fp, "Remaining object addresses:\n");
+    for (op = refchain._ob_next; op != &refchain; op = op->_ob_next)
+        fprintf(fp, "%p [%" PY_FORMAT_SIZE_T "d] %s\n", op,
+            op->ob_refcnt, Py_TYPE(op)->tp_name);
+}
+
+PyObject *
+_Py_GetObjects(PyObject *self, PyObject *args)
+{
+    int i, n;
+    PyObject *t = NULL;
+    PyObject *res, *op;
+
+    if (!PyArg_ParseTuple(args, "i|O", &n, &t))
+        return NULL;
+    op = refchain._ob_next;
+    res = PyList_New(0);
+    if (res == NULL)
+        return NULL;
+    for (i = 0; (n == 0 || i < n) && op != &refchain; i++) {
+        while (op == self || op == args || op == res || op == t ||
+               (t != NULL && Py_TYPE(op) != (PyTypeObject *) t)) {
+            op = op->_ob_next;
+            if (op == &refchain)
+                return res;
+        }
+        if (PyList_Append(res, op) < 0) {
+            Py_DECREF(res);
+            return NULL;
+        }
+        op = op->_ob_next;
+    }
+    return res;
+}
+
+#endif
+
+
+/* Hack to force loading of capsule.o */
+PyTypeObject *_Py_capsule_hack = &PyCapsule_Type;
+
+
+/* Hack to force loading of cobject.o */
+PyTypeObject *_Py_cobject_hack = &PyCObject_Type;
+
+
+/* Hack to force loading of abstract.o */
+Py_ssize_t (*_Py_abstract_hack)(PyObject *) = PyObject_Size;
+
+
+/* These methods are used to control infinite recursion in repr, str, print,
+   etc.  Container objects that may recursively contain themselves,
+   e.g. builtin dictionaries and lists, should use Py_ReprEnter() and
+   Py_ReprLeave() to avoid infinite recursion.
+
+   Py_ReprEnter() returns 0 the first time it is called for a particular
+   object and 1 every time thereafter.  It returns -1 if an exception
+   occurred.  Py_ReprLeave() has no return value.
+
+   See dictobject.c and listobject.c for examples of use.
+*/
+
+#define KEY "Py_Repr"
+
+int
+Py_ReprEnter(PyObject *obj)
+{
+    PyObject *dict;
+    PyObject *list;
+    Py_ssize_t i;
+
+    dict = PyThreadState_GetDict();
+    if (dict == NULL)
+        return 0;
+    list = PyDict_GetItemString(dict, KEY);
+    if (list == NULL) {
+        list = PyList_New(0);
+        if (list == NULL)
+            return -1;
+        if (PyDict_SetItemString(dict, KEY, list) < 0)
+            return -1;
+        Py_DECREF(list);
+    }
+    i = PyList_GET_SIZE(list);
+    while (--i >= 0) {
+        if (PyList_GET_ITEM(list, i) == obj)
+            return 1;
+    }
+    PyList_Append(list, obj);
+    return 0;
+}
+
+void
+Py_ReprLeave(PyObject *obj)
+{
+    PyObject *dict;
+    PyObject *list;
+    Py_ssize_t i;
+
+    dict = PyThreadState_GetDict();
+    if (dict == NULL)
+        return;
+    list = PyDict_GetItemString(dict, KEY);
+    if (list == NULL || !PyList_Check(list))
+        return;
+    i = PyList_GET_SIZE(list);
+    /* Count backwards because we always expect obj to be list[-1] */
+    while (--i >= 0) {
+        if (PyList_GET_ITEM(list, i) == obj) {
+            PyList_SetSlice(list, i, i + 1, NULL);
+            break;
+        }
+    }
+}
+
+/* Trashcan support. */
+
+/* Current call-stack depth of tp_dealloc calls. */
+int _PyTrash_delete_nesting = 0;
+
+/* List of objects that still need to be cleaned up, singly linked via their
+ * gc headers' gc_prev pointers.
+ */
+PyObject *_PyTrash_delete_later = NULL;
+
+/* Add op to the _PyTrash_delete_later list.  Called when the current
+ * call-stack depth gets large.  op must be a currently untracked gc'ed
+ * object, with refcount 0.  Py_DECREF must already have been called on it.
+ */
+void
+_PyTrash_deposit_object(PyObject *op)
+{
+    assert(PyObject_IS_GC(op));
+    assert(_Py_AS_GC(op)->gc.gc_refs == _PyGC_REFS_UNTRACKED);
+    assert(op->ob_refcnt == 0);
+    _Py_AS_GC(op)->gc.gc_prev = (PyGC_Head *)_PyTrash_delete_later;
+    _PyTrash_delete_later = op;
+}
+
+/* The equivalent API, using per-thread state recursion info */
+void
+_PyTrash_thread_deposit_object(PyObject *op)
+{
+    PyThreadState *tstate = PyThreadState_GET();
+    assert(PyObject_IS_GC(op));
+    assert(_Py_AS_GC(op)->gc.gc_refs == _PyGC_REFS_UNTRACKED);
+    assert(op->ob_refcnt == 0);
+    _Py_AS_GC(op)->gc.gc_prev = (PyGC_Head *) tstate->trash_delete_later;
+    tstate->trash_delete_later = op;
+}
+
+/* Dealloccate all the objects in the _PyTrash_delete_later list.  Called when
+ * the call-stack unwinds again.
+ */
+void
+_PyTrash_destroy_chain(void)
+{
+    while (_PyTrash_delete_later) {
+        PyObject *op = _PyTrash_delete_later;
+        destructor dealloc = Py_TYPE(op)->tp_dealloc;
+
+        _PyTrash_delete_later =
+            (PyObject*) _Py_AS_GC(op)->gc.gc_prev;
+
+        /* Call the deallocator directly.  This used to try to
+         * fool Py_DECREF into calling it indirectly, but
+         * Py_DECREF was already called on this object, and in
+         * assorted non-release builds calling Py_DECREF again ends
+         * up distorting allocation statistics.
+         */
+        assert(op->ob_refcnt == 0);
+        ++_PyTrash_delete_nesting;
+        (*dealloc)(op);
+        --_PyTrash_delete_nesting;
+    }
+}
+
+/* The equivalent API, using per-thread state recursion info */
+void
+_PyTrash_thread_destroy_chain(void)
+{
+    PyThreadState *tstate = PyThreadState_GET();
+    while (tstate->trash_delete_later) {
+        PyObject *op = tstate->trash_delete_later;
+        destructor dealloc = Py_TYPE(op)->tp_dealloc;
+
+        tstate->trash_delete_later =
+            (PyObject*) _Py_AS_GC(op)->gc.gc_prev;
+
+        /* Call the deallocator directly.  This used to try to
+         * fool Py_DECREF into calling it indirectly, but
+         * Py_DECREF was already called on this object, and in
+         * assorted non-release builds calling Py_DECREF again ends
+         * up distorting allocation statistics.
+         */
+        assert(op->ob_refcnt == 0);
+        ++tstate->trash_delete_nesting;
+        (*dealloc)(op);
+        --tstate->trash_delete_nesting;
+    }
+}
+
+#ifdef __cplusplus
+}
+#endif